Method and apparatus for decelerating a material reduction tool

Abstract

One embodiment of the present disclosure provides a material reduction machine including a clutch configured and arranged to engage and disengage a material reduction tool with an engine based in response to a control unit. The control unit is configured to decelerate the material reduction tool by maintaining the clutch engaged with the engine during an engine speed reduction period. Another embodiment of the present disclosure also provides a method of decelerating a material reduction tool of a material reduction machine. The method includes the steps of maintaining engagement between the material reduction tool and an engine after the engine enters an engine speed reduction mode, and disengaging the material reduction device from the engine before the engine rpm drops below a predetermined level.

Description

CROSS REFERENCES TO RELATED APPLICATIONS[0001]This application claims the benefit of U.S. Provisional Application No. 60 / 962,804, filed Jul. 31, 2007, the disclosure of which is hereby incorporated by reference in its entirety.FIELD OF THE INVENTION[0002]The present invention relates generally to material reduction machines having material reduction tools and, more specifically, to an apparatus and method for automatically and quickly decelerating the material reduction tool based on a predetermined set of conditions.BACKGROUND OF THE INVENTION[0003]Material reduction machines such as stump cutting machines are well known. Such machines commonly include a rotating cutter wheel driven by a gas or diesel engine. In the case of a stump cutter, the cutter wheel, while rotating, is advanced toward the stump and moved laterally across the face of the stump. The cutter wheel is mounted at one end of a boom which is, in turn, pivotally mounted on a support frame. Hydraulic boom swing cylind...

AI Technical Summary

Benefits of technology

The present disclosure provides a material reduction machine with a clutch that engages and disengages a material reduction tool with an engine based on a control unit. The control unit decelerates the material reduction tool by keeping the clutch engaged during an engine speed reduction period. The method involves maintaining engagement between the material reduction tool and the engine during an engine speed reduction mode and disengaging the material reduction device from the engine before the engine rpm drops below a predetermined level. The invention is not limited to a specific device and can be used in any environment where operator presence and detection is desired.

Problems solved by technology

This configuration makes sensing the presence of an operator more difficult than in most machines where the operator is seated wherein operator absence can be detected by measuring the load on the seat.

Sensing the operator's presence at the control levers of a stump cutter is further complicated by the intermittent, and sometimes simultaneous, use of the three control levers.

The combined effect results in a situation where the option of utilizing levers with mechanical or electromechanical interlocks is not practical.

Such a system also provides little freedom in repositioning the operator's hands on the levers.

Accordingly, such a system would cause fatigue, result in frequent unwanted cutter wheel stoppages, hinder operation, and create control errors.

Such difficulties are likely to cause operator rejection and provide motivation for circumventing the system.

In addition, the material reduction tools on such machines are often heavy and difficult to decelerate due to inertia of the moving tool.

Braking systems that have been developed to decelerate the material reduction tool may have less than ideal breaking torque or long term reliability.

Images